DIY base rock...a la Garf

well, on the crushed coral, i did use some of that on one of the batches of rock that i did, it was a neat effect, but i just used the coral as the molds mixed with some salt, that way some would stick to the surface and stuff...

as for mixing it into the mix itself, i've done that as well, but i really dont think your getting as much bank for you buck that way as you would just using it on the surface...

the most recent batch that i made(a few days ago) i just used 2.5 parts blue bag rock salt from homedepot, to 1 part type 1 low alk portland cement... seems like they came out good so far.. but time will tell...
Hello All,
I'm following this thread with a lot of interest, I've been wanting to try something like this for a long time you have pushed me closer.

Thanks for a great thread

Phil :Cheers:
ok you guys will laught, but i'm still curing mine LOL the supid PH will not stay down! It doesn't help that they've been curing indoors this winter, and i honestly have not been doing regular water changes. I need to get my butt in gear and put a powerhead and heater in there to maybe speed up the process. It's really my fualt. I've just been lazy. But I still have a TON of ingredients to make more than enough for my 125, so i plan to do that this summer outdoors. I'm a dork. Hehehe.
yea, i have a batch that i've not been really keeping up with the water changes on myself...

i need to find myself a kiddie pool, this last batch i made has some larger rocks in it, i'm talking 2-3 foot long, pvc skeleton ones... hehehe
Ok, so after sat on these rocks for months, leaving them just dry, I decided to call Leroy from GARF to get some advice on it. Well, turns out my worries are unfounded -- I was worried that they weren't cured yet because ph kept going up; I was also worried about having used tap water to cure it.

Well, he said the PH will always go up w/ freshwater which is why mine kept going up no matter how often I changed the water out! DUH for me! He also said using tap was perfectly fine, no worries about metals getting into the tank.

His suggestion was to take one of the smaller rocks, putting it into my tank (I'll probably stick it in the sump), and just monitoring the PH.

I was also worried cuz my rocks, since curing it outdoors again this week, started growing green stuff on it (algae)...but he says it's perfectly fine :)

I swear, I was so frustrated with the rocks. I thought I did it all wrong! VIVA La GARF!
Some pics:

I put one of the rocks in, and I'm just making sure the PH doesn't swing up, then I'll put in the rest in a couple of days. It's the crescent shaped one on the bottom left of the sump:

Hey guys, New to the forum, been running a 55gal fresh water and just got a new 55gal tank for a salt water.

Question on this DIY live rock. I have read most of this post and have a question. On one website I found they stated to do your soak/cure with vinegar, did you guys do this if so how much? Also in this website it talks about soaking for like 2 months, is this a standard time or have you guys done it in shorter periods?

I have plenty of time as I am going to take this slow. I have most of the components but need to save up for some quality lighting as the tank I have now came with a cheap hood set up, and I still have to figure out my sump set up, and I may build my own tank stand as the one that came with my freshwater tank is not being used but doesnt feel sturdy, It seems top heavy and easily wobbles with an empty tank on it.

Here are articles from -- they did a test on various ways to maybe speed up the curing process. I believe their conclusion for their particular test was that doing daily water changes and having aeration was best. I doubt the vinegar will make much difference. I used plain ole tap water in the back yard and I do daily water changes. Read up :)



PART 3 (this page is messed up, so hit "ok" and scroll down to "Rock Curing Update #3):

I also find that the rocks w/ less or no salt are stronger than the ones w/ lots of salt....for the obvious reason that it made the rock so porous, that it wasn't strong enough to hold the weight. My first batch that's in my tank now had less salt, and are very strong...the ones that I have curing right now are super porous, and are I will use those higher up in my structures, so they're not supporting have things.

Some people took less time to cure. The key is to watch your tank's PH after you put it in (See Biff's response to my PH fluctuation question: ). If you put it in, and your ph doesn't fluctuate beyond what is normal for it, then it should be fine. Otherwise, you'd have to pull it out and keep curing. Make sure you test your water for a few days prior to putting in the rock, and keep a log so you know your tank's ph fluctuations during the day

And most importantly...POST PICS!!!!
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I found the MSDS on the above quickrete coloring and the only bad ingrediant listed is Iron oxide pigmanets. Iron oxide is rust....

Thinking about it more is it even worth coloring the concrete rocks as the goal is to cover them with coraline, corals, etc?
Don't bother with coloring will be covered in coralline in no time. Plus why risk it? It's not worth the extra worry, IMHO.

Post pics and let us know if you have any more questions :D I personally LOVE making my own rocks!
Yeah I finally found another post about it on a diff forum and they said pretty much why bother because you cover it anyway.

I plan on documenting the whole build and will post when I get some more supplies and actually start the build.